It’s a 27-minute live chat in which two of my favorite independent Apple analysts, Asymco’s Horace Dediu and Techpinions’ Ben Bajarin, field questions via Twitter about the Apple Watch. Fewer than 500 people caught it as it happened, but it’s been archived for viewing anytime on Bajarin’s personal blog here.

A few highlights:

Dediu’s prediction that Apple will sell 20 million watches this year and 200 million within five years.

Their shared conviction that much of the device will be upgradable — the battery for sure, perhaps the screen, maybe even the internals, but at a price, $500 to $600, that might be prohibitive.

The smartwatch, says Dediu at one point, “is nothing more than another dot on a straight line. And that line started with big computers, got to medium computers, got to small computers, got to laptop computers, got to pocket computers, and now it’s finally wearable computers. What is it about that trajectory that tells you it cannot go any further?”

“You’ve got 2 billion transistors in your phone today,” says Bajarin, “Sometime in the very near future we’re going to have a billion transistors on your wrist. And so you say ‘what can I do in the world when I have all these sensors and a billion transistors on my wrist?’ It’s going to be crazy.”

As a proxy for success, says Dediu, “do not measure dollars. Measure minutes [of use.] How do you measure joy? How do you measure love? How do you measure fun?… Apple is not about optimization. It’s about doing the right thing. So the question is: Is this the right thing for the user? And they say: If it makes your life better, yes.”